Wind, rain, snow, ice, and other environmental conditions can cause damage to above ground utility distribution systems such as electrical utility lines supported by cross arm assemblies. Sometimes, significant structural damage may occur, including partial or complete breakage of the utility line and cross arm assembly, causing power outages, fire, and other safety hazards to humans.
For example, heavy ice or snow may accumulate on utility lines increasing the weight of the utility line and causing the utility line and cross arm assembly to break. Upon a break to the cross arm assembly, pieces of the broken cross arm often fall or pull down or break the utility line or adjacent cross arms. Further strong winds may cause utility lines to bounce up and down or “gallop.” Galloping wires generate stress upon utility lines and cross arm assemblies. This stress deteriorates, weakens, and often breaks the cross arm assembly, utility line, and adjacent cross arms. Thus, requiring the cross arm assembly to be frequently inspected, repaired, and replaced.
Cross arms are used to support conductors used in power grids. Generally, there are two main types of power grids, transmission grids and distribution grids. Transmission grids transmit highs-voltage electrical energy from power plants to substations. Distribution grids transmit low-voltage electrical energy from substations to residencies and businesses that require the power. Cross arms used in distribution grids are typically made from wood, such as timber which has been prepared for use in building and carpentry.
Unfortunately, wood cross arms are often expensive, difficult to obtain, have a limited lifespan, and require frequent maintenance and repair. Further, wood cross arms are organic and thus decay naturally over time. The typical lifespan of a wood cross arm decreases substantially when the wood cross arm is exposed to harsh environmental conditions, such as hot and cold temperatures, ice, snow, rain, and wind, for example.
To increase the lifespan and durability of wood cross arms, the wood is often treated with chemical compounds and preservatives, such as creosote, to provide ultraviolet and water protection. Creosote is a dark brown oil often distilled from coal tar that is commonly used as a wood preservative. Creosote generally includes a number of phenols, cresols, and other organic compounds. While, chemicals, such as creosote can improve the lifespan and durability of wood cross arms, such chemicals also add increased cost to the cross arm and may pose environmental concerns. Other problems presented by wood cross arms are that the wood is flammable, and thus susceptible to lightning strike-induced fires. Wood cross arms may also attract bugs and animals, such as termites and woodpeckers, who prematurely damage the structural integrity of the wood.
Wood alternatives such as fiberglass, concrete, and metal cross arms are known. Unfortunately, traditional fiberglass cross arms lack the structural strength and durability of wood cross arms and are often more expensive. Further, upon a break to a traditional fiberglass cross arm, pieces of the fiberglass cross arm fall and pull down and break the utility line. While having increased structural integrity, compared to traditional fiberglass cross arms, concrete and metal cross arms are typically heavy, making the cross arms more difficult and dangerous for workers to suspend high above the ground and more difficult to repair, inspect and replace. Further, because metal is a good conductor of electricity, metal cross arms increase the danger to lineman and other workers. Thus, lineman must take increased safety precautions when working with metal cross arms, slowing their work, increasing the cost of the work, and reducing the usefulness of metal cross arms.
In addition to the problems discussed above, traditional cross arm assemblies are not effective at reducing or preventing damage caused by galloping utility lines and environmental conditions, such as wind, ice and snow. Current cross arms are typically formed from a single unitary piece of material, generally wood, that is connected to a utility pole at a center region of the cross arm. Thus, forming a “cross” configuration between the horizontal cross arm and the vertical utility pole whereby the cross arm is divided into two substantially equal sections or halves by the utility pole. The cross arm is typically supported by v-braces, typically formed from wood, or other similar structures positioned underneath the cross arm and connected to the utility pole.
In the event the cross arm is broken or damaged, the v-brace is usually broken as well, causing pieces of the broken cross arm to fall and pull down and break the utility line, causing power outages and hazardous conditions for persons. Upon a break to the cross arm assembly, pieces of the broken cross arm often fall or pull down or break the utility line or adjacent cross arms. Further, in the event any portion of the cross arm or v-brace is damaged the entire length of the cross arm and supporting v-brace must generally be replaced, even if only one section or half of the cross arm was actually damaged or broken. Thus, increasing the cost and burden associated with replacing, repairing, and inspecting such cross arm assemblies.
To that end, it would be advantageous to provide an improved resilient cross arm assembly configured to reduce or prevent damage caused by galloping utility lines and environmental conditions such as, ice, snow, and wind. The resilient cross arm assembly includes a synthetic cross arm having a flexible housing, formed from ultraviolet resistant fiberglass for example, and includes a cable positioned within an internal chamber of the flexible housing that extends between a first end and a second end of the flexible housing. The cable is configured to prevent pieces of the synthetic cross arm from separating, falling, and pulling down and breaking the utility lines upon a break in the synthetic cross arm. Upon a break to the cross arm assembly, pieces of the broken cross arm often fall or pull down or break the utility line or adjacent cross arms.
The resilient cross arm assembly further includes a collar that is configured to attach two cross arms, for example traditional wood cross arms or synthetic cross arms, to a utility pole on opposite ends. The collar is configured so that each cross arm may flex or move vertically to absorb shock caused by galloping utility lines and heavy ice or snow. Because the collar is configured for use with two cross arms, if one cross arm is broken, only the broken cross arm would need to be replaced. Thus, increasing the cost effectiveness of the resilient cross arm assembly and decreasing the risk of injury to persons tasked with repairing, replacing, or inspecting the resilient cross arm assembly. It is to such a resilient cross arm assembly and to methods for using thereof that exemplary embodiments of the inventive concepts disclosed and claimed herein are directed.